Police investigating the murder of a university lecturer in southwest London have released CCTV footage showing him walking along a road shortly before he was killed.

Daniel Young, 30, was stabbed in Morden last Tuesday.

The footage shows Mr Young with a laptop and bag over his shoulder as he walks along a road towards the entrance to Kendor Gardens.

He turned into the road at around 8am and was stabbed within minutes.

Metropolitan Police's Detective Chief Inspector Cliff Lyons, who is the officer in charge, said: "Exactly a week ago today, Daniel left home to go to work.

"He had no reason to suspect he was going to be attacked and there is still no clear motive, or reason, for what appears to be the senseless murder of a brilliant young man.

"I believe his attacker left the park immediately after he attacked him and did so via the Dorset Road entrance. I am appealing for anyone who was nearby and saw something, however insignificant it may seem, to contact the incident room.

"The response from the public so far has been incredibly helpful and both I, and Daniel's family, are very grateful. However, we still need anyone who was in the vicinity of Kendor Gardens and Dorset Road, at that time of day to get in touch.

"I would also be interested in speaking to anyone in the area who has a recording device, perhaps on their car, cycling helmet, or private CCTV, we have not yet seen. It is possible they could have captured something of interest to me.

"The investigation has continued to move at a fast pace, and there have been a number of arrests.

"My detectives continue to review many hours of CCTV and have already spoken to and taken a large amount of witness statements. However, I again reiterate appeals to anyone with information to come forward.

"I would like to reassure people, particularly the residents of Morden, that attacks of this nature are rare and uniformed police officers from Merton Borough continue to patrol the area and provide a visible reassurance to the community."

A 26-year-old man and 35-year-old man have been arrested on suspicion of murder and both were subsequently bailed.

Anyone with any information is asked to contact the incident room on 020 8721 4961 or Crimestoppers anonymously on 0800 555 111.